contestada

A race driver has made a pit stop to refuel. after refueling, he leaves the pit area with an acceleration whose magnitude is 6.35 m/s2; after 4.0 s he enters the main speedway. at the same instant, another car on the speedway and traveling at a constant speed of 73 m/s overtakes and passes the entering car. if the entering car maintains its acceleration, how much time is required for it to catch the other car? s

Respuesta :

V₀=6.35*4=25.4 m/s the speed of the when  car enters into main speedway
S=V₂t
S=73t - distance of the second car
S=V₀t+at²/2
S=25.4t+6.35t²/2 - distance of the first car
6.35t²/2+25.4t=73t
t*(3.175t-47.6)
3.175t=47.6
t=14.99 s

14.99 s is required for the first car to catch the second